kernel-aes67/drivers/gpio/gpio-npcm-sgpio.c

620 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Nuvoton NPCM Serial GPIO Driver
*
* Copyright (C) 2021 Nuvoton Technologies
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/gpio/driver.h>
#include <linux/hashtable.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/units.h>
#define MAX_NR_HW_SGPIO 64
#define NPCM_IOXCFG1 0x2A
#define NPCM_IOXCFG1_SFT_CLK GENMASK(3, 0)
#define NPCM_IOXCFG1_SCLK_POL BIT(4)
#define NPCM_IOXCFG1_LDSH_POL BIT(5)
#define NPCM_IOXCTS 0x28
#define NPCM_IOXCTS_IOXIF_EN BIT(7)
#define NPCM_IOXCTS_RD_MODE GENMASK(2, 1)
#define NPCM_IOXCTS_RD_MODE_PERIODIC BIT(2)
#define NPCM_IOXCFG2 0x2B
#define NPCM_IOXCFG2_PORT GENMASK(3, 0)
#define NPCM_IXOEVCFG_MASK GENMASK(1, 0)
#define NPCM_IXOEVCFG_FALLING BIT(1)
#define NPCM_IXOEVCFG_RISING BIT(0)
#define NPCM_IXOEVCFG_BOTH (NPCM_IXOEVCFG_FALLING | NPCM_IXOEVCFG_RISING)
#define NPCM_CLK_MHZ (8 * HZ_PER_MHZ)
#define NPCM_750_OPT 6
#define NPCM_845_OPT 5
#define GPIO_BANK(x) ((x) / 8)
#define GPIO_BIT(x) ((x) % 8)
/*
* Select the frequency of shift clock.
* The shift clock is a division of the APB clock.
*/
struct npcm_clk_cfg {
unsigned int *sft_clk;
unsigned int *clk_sel;
unsigned int cfg_opt;
};
struct npcm_sgpio {
struct gpio_chip chip;
struct clk *pclk;
struct irq_chip intc;
raw_spinlock_t lock;
void __iomem *base;
int irq;
u8 nin_sgpio;
u8 nout_sgpio;
u8 in_port;
u8 out_port;
u8 int_type[MAX_NR_HW_SGPIO];
};
struct npcm_sgpio_bank {
u8 rdata_reg;
u8 wdata_reg;
u8 event_config;
u8 event_status;
};
enum npcm_sgpio_reg {
READ_DATA,
WRITE_DATA,
EVENT_CFG,
EVENT_STS,
};
static const struct npcm_sgpio_bank npcm_sgpio_banks[] = {
{
.wdata_reg = 0x00,
.rdata_reg = 0x08,
.event_config = 0x10,
.event_status = 0x20,
},
{
.wdata_reg = 0x01,
.rdata_reg = 0x09,
.event_config = 0x12,
.event_status = 0x21,
},
{
.wdata_reg = 0x02,
.rdata_reg = 0x0a,
.event_config = 0x14,
.event_status = 0x22,
},
{
.wdata_reg = 0x03,
.rdata_reg = 0x0b,
.event_config = 0x16,
.event_status = 0x23,
},
{
.wdata_reg = 0x04,
.rdata_reg = 0x0c,
.event_config = 0x18,
.event_status = 0x24,
},
{
.wdata_reg = 0x05,
.rdata_reg = 0x0d,
.event_config = 0x1a,
.event_status = 0x25,
},
{
.wdata_reg = 0x06,
.rdata_reg = 0x0e,
.event_config = 0x1c,
.event_status = 0x26,
},
{
.wdata_reg = 0x07,
.rdata_reg = 0x0f,
.event_config = 0x1e,
.event_status = 0x27,
},
};
static void __iomem *bank_reg(struct npcm_sgpio *gpio,
const struct npcm_sgpio_bank *bank,
const enum npcm_sgpio_reg reg)
{
switch (reg) {
case READ_DATA:
return gpio->base + bank->rdata_reg;
case WRITE_DATA:
return gpio->base + bank->wdata_reg;
case EVENT_CFG:
return gpio->base + bank->event_config;
case EVENT_STS:
return gpio->base + bank->event_status;
default:
/* actually if code runs to here, it's an error case */
dev_WARN(gpio->chip.parent, "Getting here is an error condition");
return NULL;
}
}
static const struct npcm_sgpio_bank *offset_to_bank(unsigned int offset)
{
unsigned int bank = GPIO_BANK(offset);
return &npcm_sgpio_banks[bank];
}
static void npcm_sgpio_irqd_to_data(struct irq_data *d,
struct npcm_sgpio **gpio,
const struct npcm_sgpio_bank **bank,
u8 *bit, unsigned int *offset)
{
struct npcm_sgpio *internal;
*offset = irqd_to_hwirq(d);
internal = irq_data_get_irq_chip_data(d);
*gpio = internal;
*offset -= internal->nout_sgpio;
*bank = offset_to_bank(*offset);
*bit = GPIO_BIT(*offset);
}
static int npcm_sgpio_init_port(struct npcm_sgpio *gpio)
{
u8 in_port, out_port, set_port, reg;
in_port = GPIO_BANK(gpio->nin_sgpio);
if (GPIO_BIT(gpio->nin_sgpio) > 0)
in_port += 1;
out_port = GPIO_BANK(gpio->nout_sgpio);
if (GPIO_BIT(gpio->nout_sgpio) > 0)
out_port += 1;
gpio->in_port = in_port;
gpio->out_port = out_port;
set_port = (out_port & NPCM_IOXCFG2_PORT) << 4 |
(in_port & NPCM_IOXCFG2_PORT);
iowrite8(set_port, gpio->base + NPCM_IOXCFG2);
reg = ioread8(gpio->base + NPCM_IOXCFG2);
return reg == set_port ? 0 : -EINVAL;
}
static int npcm_sgpio_dir_in(struct gpio_chip *gc, unsigned int offset)
{
struct npcm_sgpio *gpio = gpiochip_get_data(gc);
return offset < gpio->nout_sgpio ? -EINVAL : 0;
}
static int npcm_sgpio_dir_out(struct gpio_chip *gc, unsigned int offset, int val)
{
gc->set(gc, offset, val);
return 0;
}
static int npcm_sgpio_get_direction(struct gpio_chip *gc, unsigned int offset)
{
struct npcm_sgpio *gpio = gpiochip_get_data(gc);
if (offset < gpio->nout_sgpio)
return GPIO_LINE_DIRECTION_OUT;
return GPIO_LINE_DIRECTION_IN;
}
static void npcm_sgpio_set(struct gpio_chip *gc, unsigned int offset, int val)
{
struct npcm_sgpio *gpio = gpiochip_get_data(gc);
const struct npcm_sgpio_bank *bank = offset_to_bank(offset);
void __iomem *addr;
u8 reg = 0;
addr = bank_reg(gpio, bank, WRITE_DATA);
reg = ioread8(addr);
if (val)
reg |= BIT(GPIO_BIT(offset));
else
reg &= ~BIT(GPIO_BIT(offset));
iowrite8(reg, addr);
}
static int npcm_sgpio_get(struct gpio_chip *gc, unsigned int offset)
{
struct npcm_sgpio *gpio = gpiochip_get_data(gc);
const struct npcm_sgpio_bank *bank;
void __iomem *addr;
u8 reg;
if (offset < gpio->nout_sgpio) {
bank = offset_to_bank(offset);
addr = bank_reg(gpio, bank, WRITE_DATA);
} else {
offset -= gpio->nout_sgpio;
bank = offset_to_bank(offset);
addr = bank_reg(gpio, bank, READ_DATA);
}
reg = ioread8(addr);
return !!(reg & BIT(GPIO_BIT(offset)));
}
static void npcm_sgpio_setup_enable(struct npcm_sgpio *gpio, bool enable)
{
u8 reg;
reg = ioread8(gpio->base + NPCM_IOXCTS);
reg = (reg & ~NPCM_IOXCTS_RD_MODE) | NPCM_IOXCTS_RD_MODE_PERIODIC;
if (enable)
reg |= NPCM_IOXCTS_IOXIF_EN;
else
reg &= ~NPCM_IOXCTS_IOXIF_EN;
iowrite8(reg, gpio->base + NPCM_IOXCTS);
}
static int npcm_sgpio_setup_clk(struct npcm_sgpio *gpio,
const struct npcm_clk_cfg *clk_cfg)
{
unsigned long apb_freq;
u32 val;
u8 tmp;
int i;
apb_freq = clk_get_rate(gpio->pclk);
tmp = ioread8(gpio->base + NPCM_IOXCFG1) & ~NPCM_IOXCFG1_SFT_CLK;
for (i = clk_cfg->cfg_opt-1; i > 0; i--) {
val = apb_freq / clk_cfg->sft_clk[i];
if (NPCM_CLK_MHZ > val) {
iowrite8(clk_cfg->clk_sel[i] | tmp,
gpio->base + NPCM_IOXCFG1);
return 0;
}
}
return -EINVAL;
}
static void npcm_sgpio_irq_init_valid_mask(struct gpio_chip *gc,
unsigned long *valid_mask,
unsigned int ngpios)
{
struct npcm_sgpio *gpio = gpiochip_get_data(gc);
/* input GPIOs in the high range */
bitmap_set(valid_mask, gpio->nout_sgpio, gpio->nin_sgpio);
bitmap_clear(valid_mask, 0, gpio->nout_sgpio);
}
static void npcm_sgpio_irq_set_mask(struct irq_data *d, bool set)
{
const struct npcm_sgpio_bank *bank;
struct npcm_sgpio *gpio;
unsigned long flags;
void __iomem *addr;
unsigned int offset;
u16 reg, type;
u8 bit;
npcm_sgpio_irqd_to_data(d, &gpio, &bank, &bit, &offset);
addr = bank_reg(gpio, bank, EVENT_CFG);
reg = ioread16(addr);
if (set) {
reg &= ~(NPCM_IXOEVCFG_MASK << (bit * 2));
} else {
type = gpio->int_type[offset];
reg |= (type << (bit * 2));
}
raw_spin_lock_irqsave(&gpio->lock, flags);
npcm_sgpio_setup_enable(gpio, false);
iowrite16(reg, addr);
npcm_sgpio_setup_enable(gpio, true);
addr = bank_reg(gpio, bank, EVENT_STS);
reg = ioread8(addr);
reg |= BIT(bit);
iowrite8(reg, addr);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
}
static void npcm_sgpio_irq_ack(struct irq_data *d)
{
const struct npcm_sgpio_bank *bank;
struct npcm_sgpio *gpio;
unsigned long flags;
void __iomem *status_addr;
unsigned int offset;
u8 bit;
npcm_sgpio_irqd_to_data(d, &gpio, &bank, &bit, &offset);
status_addr = bank_reg(gpio, bank, EVENT_STS);
raw_spin_lock_irqsave(&gpio->lock, flags);
iowrite8(BIT(bit), status_addr);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
}
static void npcm_sgpio_irq_mask(struct irq_data *d)
{
npcm_sgpio_irq_set_mask(d, true);
}
static void npcm_sgpio_irq_unmask(struct irq_data *d)
{
npcm_sgpio_irq_set_mask(d, false);
}
static int npcm_sgpio_set_type(struct irq_data *d, unsigned int type)
{
const struct npcm_sgpio_bank *bank;
irq_flow_handler_t handler;
struct npcm_sgpio *gpio;
unsigned long flags;
void __iomem *addr;
unsigned int offset;
u16 reg, val;
u8 bit;
npcm_sgpio_irqd_to_data(d, &gpio, &bank, &bit, &offset);
switch (type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_EDGE_BOTH:
val = NPCM_IXOEVCFG_BOTH;
break;
case IRQ_TYPE_EDGE_RISING:
case IRQ_TYPE_LEVEL_HIGH:
val = NPCM_IXOEVCFG_RISING;
break;
case IRQ_TYPE_EDGE_FALLING:
case IRQ_TYPE_LEVEL_LOW:
val = NPCM_IXOEVCFG_FALLING;
break;
default:
return -EINVAL;
}
if (type & IRQ_TYPE_LEVEL_MASK)
handler = handle_level_irq;
else
handler = handle_edge_irq;
gpio->int_type[offset] = val;
raw_spin_lock_irqsave(&gpio->lock, flags);
npcm_sgpio_setup_enable(gpio, false);
addr = bank_reg(gpio, bank, EVENT_CFG);
reg = ioread16(addr);
reg |= (val << (bit * 2));
iowrite16(reg, addr);
npcm_sgpio_setup_enable(gpio, true);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
irq_set_handler_locked(d, handler);
return 0;
}
static void npcm_sgpio_irq_handler(struct irq_desc *desc)
{
struct gpio_chip *gc = irq_desc_get_handler_data(desc);
struct irq_chip *ic = irq_desc_get_chip(desc);
struct npcm_sgpio *gpio = gpiochip_get_data(gc);
unsigned int i, j, girq;
unsigned long reg;
chained_irq_enter(ic, desc);
for (i = 0; i < ARRAY_SIZE(npcm_sgpio_banks); i++) {
const struct npcm_sgpio_bank *bank = &npcm_sgpio_banks[i];
reg = ioread8(bank_reg(gpio, bank, EVENT_STS));
for_each_set_bit(j, &reg, 8) {
girq = irq_find_mapping(gc->irq.domain,
i * 8 + gpio->nout_sgpio + j);
generic_handle_domain_irq(gc->irq.domain, girq);
}
}
chained_irq_exit(ic, desc);
}
static const struct irq_chip sgpio_irq_chip = {
.name = "sgpio-irq",
.irq_ack = npcm_sgpio_irq_ack,
.irq_mask = npcm_sgpio_irq_mask,
.irq_unmask = npcm_sgpio_irq_unmask,
.irq_set_type = npcm_sgpio_set_type,
.flags = IRQCHIP_IMMUTABLE | IRQCHIP_MASK_ON_SUSPEND,
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
static int npcm_sgpio_setup_irqs(struct npcm_sgpio *gpio,
struct platform_device *pdev)
{
int rc, i;
struct gpio_irq_chip *irq;
rc = platform_get_irq(pdev, 0);
if (rc < 0)
return rc;
gpio->irq = rc;
npcm_sgpio_setup_enable(gpio, false);
/* Disable IRQ and clear Interrupt status registers for all SGPIO Pins. */
for (i = 0; i < ARRAY_SIZE(npcm_sgpio_banks); i++) {
const struct npcm_sgpio_bank *bank = &npcm_sgpio_banks[i];
iowrite16(0, bank_reg(gpio, bank, EVENT_CFG));
iowrite8(0xff, bank_reg(gpio, bank, EVENT_STS));
}
irq = &gpio->chip.irq;
gpio_irq_chip_set_chip(irq, &sgpio_irq_chip);
irq->init_valid_mask = npcm_sgpio_irq_init_valid_mask;
irq->handler = handle_bad_irq;
irq->default_type = IRQ_TYPE_NONE;
irq->parent_handler = npcm_sgpio_irq_handler;
irq->parent_handler_data = gpio;
irq->parents = &gpio->irq;
irq->num_parents = 1;
return 0;
}
static int npcm_sgpio_probe(struct platform_device *pdev)
{
struct npcm_sgpio *gpio;
const struct npcm_clk_cfg *clk_cfg;
int rc;
u32 nin_gpios, nout_gpios;
gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
if (!gpio)
return -ENOMEM;
gpio->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(gpio->base))
return PTR_ERR(gpio->base);
clk_cfg = device_get_match_data(&pdev->dev);
if (!clk_cfg)
return -EINVAL;
rc = device_property_read_u32(&pdev->dev, "nuvoton,input-ngpios",
&nin_gpios);
if (rc < 0)
return dev_err_probe(&pdev->dev, rc, "Could not read ngpios property\n");
rc = device_property_read_u32(&pdev->dev, "nuvoton,output-ngpios",
&nout_gpios);
if (rc < 0)
return dev_err_probe(&pdev->dev, rc, "Could not read ngpios property\n");
gpio->nin_sgpio = nin_gpios;
gpio->nout_sgpio = nout_gpios;
if (gpio->nin_sgpio > MAX_NR_HW_SGPIO ||
gpio->nout_sgpio > MAX_NR_HW_SGPIO)
return dev_err_probe(&pdev->dev, -EINVAL, "Number of GPIOs exceeds the maximum of %d: input: %d output: %d\n", MAX_NR_HW_SGPIO, nin_gpios, nout_gpios);
gpio->pclk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(gpio->pclk))
return dev_err_probe(&pdev->dev, PTR_ERR(gpio->pclk), "Could not get pclk\n");
rc = npcm_sgpio_setup_clk(gpio, clk_cfg);
if (rc < 0)
return dev_err_probe(&pdev->dev, rc, "Failed to setup clock\n");
raw_spin_lock_init(&gpio->lock);
gpio->chip.parent = &pdev->dev;
gpio->chip.ngpio = gpio->nin_sgpio + gpio->nout_sgpio;
gpio->chip.direction_input = npcm_sgpio_dir_in;
gpio->chip.direction_output = npcm_sgpio_dir_out;
gpio->chip.get_direction = npcm_sgpio_get_direction;
gpio->chip.get = npcm_sgpio_get;
gpio->chip.set = npcm_sgpio_set;
gpio->chip.label = dev_name(&pdev->dev);
gpio->chip.base = -1;
rc = npcm_sgpio_init_port(gpio);
if (rc < 0)
return rc;
rc = npcm_sgpio_setup_irqs(gpio, pdev);
if (rc < 0)
return rc;
rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
if (rc)
return dev_err_probe(&pdev->dev, rc, "GPIO registering failed\n");
npcm_sgpio_setup_enable(gpio, true);
return 0;
}
static unsigned int npcm750_SFT_CLK[NPCM_750_OPT] = {
1024, 32, 8, 4, 3, 2,
};
static unsigned int npcm750_CLK_SEL[NPCM_750_OPT] = {
0x00, 0x05, 0x07, 0x0C, 0x0D, 0x0E,
};
static unsigned int npcm845_SFT_CLK[NPCM_845_OPT] = {
1024, 32, 16, 8, 4,
};
static unsigned int npcm845_CLK_SEL[NPCM_845_OPT] = {
0x00, 0x05, 0x06, 0x07, 0x0C,
};
static struct npcm_clk_cfg npcm750_sgpio_pdata = {
.sft_clk = npcm750_SFT_CLK,
.clk_sel = npcm750_CLK_SEL,
.cfg_opt = NPCM_750_OPT,
};
static const struct npcm_clk_cfg npcm845_sgpio_pdata = {
.sft_clk = npcm845_SFT_CLK,
.clk_sel = npcm845_CLK_SEL,
.cfg_opt = NPCM_845_OPT,
};
static const struct of_device_id npcm_sgpio_of_table[] = {
{ .compatible = "nuvoton,npcm750-sgpio", .data = &npcm750_sgpio_pdata, },
{ .compatible = "nuvoton,npcm845-sgpio", .data = &npcm845_sgpio_pdata, },
{}
};
MODULE_DEVICE_TABLE(of, npcm_sgpio_of_table);
static struct platform_driver npcm_sgpio_driver = {
.driver = {
.name = KBUILD_MODNAME,
.of_match_table = npcm_sgpio_of_table,
},
.probe = npcm_sgpio_probe,
};
module_platform_driver(npcm_sgpio_driver);
MODULE_AUTHOR("Jim Liu <jjliu0@nuvoton.com>");
MODULE_AUTHOR("Joseph Liu <kwliu@nuvoton.com>");
MODULE_DESCRIPTION("Nuvoton NPCM Serial GPIO Driver");
MODULE_LICENSE("GPL v2");